1. Field of the Invention
The present invention relates to heat dissipation devices, and particularly to a heat dissipation device having a heat pipe for cooling an electronic component, such as an integrated circuit package.
2. Description of Related Art
During operation of an electronic device such as a computer central processing unit (CPU), a large amount of heat is often produced. The heat must be quickly removed from the CPU to prevent it from becoming unstable or being damaged. Typically, a heat dissipation device is attached to an outer surface of the CPU to absorb the heat from the CPU. The heat absorbed by the heat dissipation device is then dissipated to ambient air.
Conventionally, a heat dissipation device comprises a solid metal base attached to the CPU, and a plurality of fins arranged on the base. The base is intimately attached to the CPU thereby absorbing the heat generated by the CPU. Most of the heat accumulated on the base is transferred firstly to the fins and then dissipates away from the fins. However, as electronics technology continues to advance, increasing amounts of heat are being generated by powerful state-of-the-art CPUs. As a result, many conventional heat dissipation devices are no longer able to effectively remove heat from these CPUs.
In order to overcome the above set out problems, one type of heat dissipation device used with the electronic devices includes a heat pipe for transferring heat from one part of the heat dissipation device to another. A heat pipe is a vacuum-sealed pipe that is filled with a phase changeable material, usually being a liquid, such as water, alcohol, acetone or the like, and has an inner wall thereof covered with a capillary configuration. As the electronic device heats up, a hot section (usually called an evaporating section) of the heat pipe, which is located close to the electronic device, also heats up. The liquid in the evaporating section of the heat pipe evaporates and the resultant vapor reaches a cool section (usually called a condensing section) of the heat pipe and condenses therein. Then the condensed liquid flows to the evaporating section along the capillary configuration of the heat pipe. This evaporation/condensation cycle repeats and since the heat pipe transfers heat so efficiently, the evaporating section is kept at or near the same temperature as the condensing section of the heat pipe. Correspondingly, heat-transfer capability of the heat dissipation device including such a heat pipe is greatly improved.
A heat dissipation device may incorporate a plurality of heat pipes. The heat dissipation device further comprises a base for contacting an electronic device and a plurality of fins arranged on the base. The base defines a plurality of grooves therein. The fins cooperatively define a plurality of through holes therein. Each heat pipe is generally U-shaped and has a substantially straight evaporating section received in a corresponding groove of the base, a straight condensing section received in a corresponding through hole of the fins. The heat generated by the electronic device is absorbed by the base, and transferred from the base to the fins via the heat pipes, and finally dissipated from the fins to ambient air. However, in order to improve heat dissipation efficiency of the heat dissipation device, the number of the heat pipes is increased, which accordingly increases the cost of the heat dissipation device.
What is needed, therefore, is a heat dissipation device which has a greater heat-transfer capability whilst remaining economical to produce. More specifically, the present invention is aimed to enhance the heat dissipation capability of the heat dissipation device without increasing the number of the heat pipes.